1. Technical Field
The present invention relates to wireless communications and, more particularly, to management of radio frequency resources in wireless communication systems.
2. Description of Related Art
More people than ever are using mobile stations, such as cell phones and personal digital assistants (PDAs), to connect to wireless wide area networks (WWANs), which are also referred to as wireless communication systems, cellular communication systems, wireless networks, radio access networks, wireless access networks, and by other names. Service providers typically operate these WWANs to provide both voice and data services using a wireless communication format such as Code Division Multiple Access (CDMA), or another format.
Service providers typically operate multiple base stations with which the mobile stations may communicate. Each base station typically takes the form of a base transceiver station (BTS) controlled by a base station controller (BSC), which acts as a conduit for signaling and bearer communication between (i) an RF air interface over which the BTS communicates with mobile stations and (ii) a mobile switching center (MSC) and/or a packet data serving node (PDSN). The MSC and/or PDSN provide one or more interfaces between the BSC and one or more signaling and transport networks, enabling mobile stations to communicate with other devices.
Each base station is typically capable of communicating over the air interface with mobile stations on one or more carrier frequencies (carriers). Furthermore, each base station is typically capable of communicating with a finite number of mobile stations on each carrier. Thus, the greater the number of carriers on which a base station is operating at a given time, the greater the number of mobile stations the base station can serve at that time.
Service providers typically purchase base stations capable of operating on a number of carriers, perhaps five as an example. Manufacturers typically design base stations such that, for each carrier on which a service provider wants a base station to operate, the service provider must purchase a keycode, which is essentially a password that unlocks the base station's ability to operate on a carrier. Manufacturers can thus require service providers to separately pay for the base-station hardware and keycodes for each carrier on which the base station will operate.
It is often the case that a base price paid by a service provider for a base station would include at least one or two keycodes, such that the base station could at least be minimally operational. If, at the time of purchase, the service provider wishes to deploy the base station in a high-demand service area that would typically serve a large number of mobile stations, the service provider may choose to purchase additional keycodes so that the base station can operate on a higher number of carriers. If the service provider does not exercise this option initially, but then wishes to redeploy a base station in a high-demand area, or decides that the base station's number of carriers is insufficient, the service provider must pay for additional keycodes from the manufacturer, and configure the base station accordingly.
If a service provider overestimates the number of carriers a base station will need, the service provider may overspend. If the service provider underestimates the number of carriers a base station will need, the service provider must either accept that the base station may not always meet the demands placed on it, or incur the costs of increasing the base station's number of carriers. Also, some base stations occasionally experience expected or unexpected surges in demand, perhaps due to events or emergencies. Furthermore, not only must a service provider attempt to select the optimal number of carriers for each base station, but also the correct carriers for each base station to use, to maximize network performance and quality of user experience.